FI105128B - Cover for drive shaft - Google Patents

Description

Cover for drive shaft 105128

This invention relates to a protective cover, in particular for a drive shaft of motor vehicles, such as tractors 5, which has a substantially U-shaped main part according to the preamble of claim 1.

Work vehicles, such as agricultural and industrial tractors, are equipped with a protruding drive shaft (PTO) that transmits power to the outboard implements or other implements. The speed of rotation of this drive shaft is typically a few hundred revolutions per minute and can therefore constitute a hazard when openly accessible. For this reason, a U-shaped covering part covering the top and sides of the drive shaft is often used to provide shielding, such as that disclosed in U.S. Patent 2,443,035, which has the features of the preamble of claim 15. In this case, the cover part must not be too close to the drive shaft, since it is also conventional (U.S. Patent 3,462,975) to use shields surrounding the drive shaft which rotate together with the shaft. In addition, there is sufficient space inside the U-shaped main roof to receive the guard rails of the coupling device.

20 Due to the main guard over the drive shaft, it is difficult to connect the coupling shaft to the drive shaft. For this reason, it has been previously proposed, for example, through U.S. Patent 3,389,763, to use a removable protective cover. However, some people have removed the protective cover and have not re-fitted it during use, leaving the drive shaft unprotected. For this reason, reversible guardrails were developed, such as U.S. Patent Re. 30,152 is known.

However, these upside-down shields also have certain drawbacks. Many commercial vehicles 30 are equipped with a three-point coupling device which surrounds the drive shaft. In this case, the upper link arm of the three-point coupling device is generally located directly above the main protective cover of the drive shaft. When the coupling device is lowered too far down, the upper support arm can strike and damage the main guard. For this reason, U.S. Patent No. 2,105,128 4,553,950 proposes a main protective cover, in which the risk of damage is reduced so that the protective cover can be turned not only upwards but also downwards.

5 However, the latter solution also has the disadvantage that its reliability depends on the exact working method of the operator. The operator may not lower the guard rail before lowering the upper support arm. In this case, the upper arm may strike the barrier and damage it. If this guard is not installed or replaced, the vehicle will operate again without a reliable guard plate for the drive shaft 10.

In addition, the operator may also leave the folded up shield down again after engaging in the protective position before putting the machine into operation. In this case it is very likely that the upper arm will strike the main shield and again 15 will damage this.

The object of the present invention is to provide a cover for the type of taper shafts of the above type, which can be depressed, for example, by means of the upper arm, without damaging the cover and thereby maintaining the reliable protection of the taper shaft. Another function is to form the protective cover so that the folded up protective cover can be lowered to the operating position by the • upper arm.

This object is solved by this type of guardrail according to the invention in accordance with the characterizing part of claim 1 of claim 25. The cover is provided with a pivoting, pre-tensioned central flap at its upper surface. If the guard is in its normal operating position and the upper arm is lowered too low, the upper arm simply flaps down. If the upper link arm is raised again, the spring-biased flap will swing back up to the normal operating position.

30 The flap can also be used to move the main body of the guard to normal use— · position with the main body up and the upper arm pressed against the flap 3 105128. The main part of the guard can be swiveled around the pivoting pivots. The pivot pins are arranged in the slots in the guardrail so that the main body can also be moved along the slits. However, the flap cannot be moved, but only pivoted about the pivot pins. The flap is provided with a tongue 5 that can engage the upper end of the guard when the latter is in its raised position. However, the tab does not grip the protective cover when it is lowered to its normal working position.

The guard rests in its raised position on the pivot pin located at one end of the slot 10. The guard will then be in a stable position. In this position, the flap tab sticks to the protective cover. When the upper support arm presses the flap down from this position, it pivots about the pivot pin and the tongue lifts the guard so that the pivot point of the guard guard moves along the slot to the other end of the slot. As the pivot pin moves from one end of the slot to the other, the flap spring is tensioned, after which it flaps again because the spring is at its maximum between the slot ends. Thus, a spin-motion effect is created which, together with gravity, pushes the guard down to its normal working position. By moving the upper arm further down, the center flap, as already described, can be pressed down as needed.

From this it is evident that the present invention has provided a tap guard shaft cover which will not be damaged when lowering the upper link arm, regardless of the position in which the operator has left the guard.

Other suitable embodiments and further developments of the invention will be apparent from the subclaims.

The invention, as well as other advantages and further embodiments of the invention, will be explained in more detail with reference to the drawing which illustrates an embodiment of the invention, and in which:

Fig. 1 is a perspective view of the transmission shaft at the rear end of the tractor, according to the invention, 4 105128

Figure 2 shows the protective cover of Figure 1 in the normal position,

Fig. 3 is a side view of the protective cover taken along line 3-3 of Fig. 2, in normal working position;

Fig. 4 is a cross-sectional view of the protective cover taken along line 4-4 of Fig. 2 with the center flap pressed against by the upper arm;

Fig. 5 is a cross-sectional view of the guard over the line 5-5 of Fig. 2 with the guard 10 in the raised position; and

Figure 6 shows in detail an alternative embodiment of the central flap of the protective cover of Figure 1.

Figure 1 shows a protective cover 10 for the free end of the drive shaft 14 projecting outside the rear end of the tractor 12. The tractor 12 is provided with a three-point linkage device (only partially shown) comprising two lower link arms 16 and one upper link arm 18, which is grouped around the protective cover.

According to Figures 1 and 2, the cover 10 according to the invention consists of two main parts, i.e. a main part 20 and a central flap 22. The flap 22 makes it possible to close the notch area 24 of the main part 20. As will be explained below, the flap 22 is biased upwardly the main 20 notches 24.

2 and 3, the side portions of the main body 20 are substantially perpendicular, with the edges preferably being rounded. Both the main body 20 and also the flap 22 can be pivoted about pivot pins 26 which, by means of supports 27, are fixedly mounted on the rear of the tractor. Preferably, two pivot pins 26 are used, i.e. one on each side of the shroud 20 on each side of the drive shaft (4). Alternatively, a single rod 26 'extending between each side of the shield 20 may also be used, as can be seen from Figure 6.

The flap 22 comprises a main closure portion 28 by means of which the notch region 24 of the main portion 20 is closed in a normal position. Both the main part 20 and the flap 22 are preferably provided with upwardly bent edges 30, 32 at their outer ends.

The flap 22 further comprises an intermediate region 34 connecting the flap 22 of the main closure portion 28 to the regions 36 associated with the pivot pins 26. The intermediate regions 34 of the flap 22 are shaped such that the main closure portion 28 is pressed against the upper outer surface of the main portion 20

10, one end of the tension spring 40 is suspended from a hole 42 in the spring 40 and the other end of the spring 40 is suspended from the other end of the spring 40. a spring pendant 46 in the bore 44 formed by an inwardly bent portion of the adjacent side wall 15 of the shroud 10. The spring pendant 46 is best illustrated in Figure 1. The normal function of the springs 40 is to prestress the main closure portion 28 of the flap 22 against the upper outer surface of the main portion 20 of the shield 10 so that the notch 24 is closed.

As can be seen from Figure 4, the upper support arm 18 is pressed far down when lowered against the bent edge 32 of the flap 22. The width of the flap 22 and the notch 24 is determined such that, even when the protective cover 10 is rotated at a maximum * horizontally, the upper support arm 18 contacts only this part of the flap 22. As a result of such action and while lowering the upper arm 18, the flap 22 is pressed down to pivot about the pivot pins 26 25 and to stretch the tension springs 40. As the subsequent upper arm 18 is lifted, the springs 40 retract and lift the flap 22 back to its normal position. 3 is shown. It will be appreciated that this lowering of the upper support arm 18 will not cause any damage to the protective cover 10.

30 To secure accessibility to the drive shaft 14 during engagement or disconnection, the cover 10 may be folded up around the pivot pins 26. The stable upward position of the guard 10 · 'is achieved by the chamfer grooves 50 in the lateral portions 6 105128 of the main portion 20 and the upper portions 20 in the upper corners towards the rear of the tractor. The main portion 20 is particularly supported by pivot bearings 48 on pivot pins 26. The length and position of the pockets are selected with respect to pivot pins 26, spring pivots 38, springs 40, and spring pendants 46 such that pivots 26 are at one end of pivot 48 a on one side of the springs 40, and when the pivot pins 26 are located at one end of the slot 48, there is a pivot point b on the other side of the springs 40. Since the flap 22 and its spring pendant 38 are fixed with respect to the pivot point 26 and not the main part 20, an impulse movement or over-center arrangement is obtained. As the main body 20 is moved between the raised and 10 lowered positions, the pins 26 move along slots 48 from one end position to the other.

During this transfer, the springs 40 initially stretch, after which they retract again. The maximum length of the springs is between the end positions. This means that the ends of the slots 48 form stable positions. The purpose of the chamfer 50 of the main body 20 is to secure the protective cover 10 by leaning on the rear part 12 of the tractor when the protective cover 10 is in the raised position. The pivot pin 26 is then at pivot point a, as shown in Figure 5. Instead, when the pivot pin 26 is located at the pivot point b, it will position itself in a stable position 20 through the abutment of the rim 52 of the main body 20 against the rear part 12 of the tractor as shown in Figures 3 and 4.

The central flap 22 may also be used to move the protective cover 10 down to its normal position. This is achieved by contact between it and the upper support arm 18 when the operator has left the protective cover 10 in the raised position shown in Fig. 5. The flap 22 is provided on each side with lifting tabs 54 which may project into the lifting slots 56 on the upper outer surface of the main body 20. Referring to FIG. 30 Nostokielekkeet 54 then moving in the direction of the arrow 58 and pressed against the edges 56 nostorakojen. In this case, the main part 20 increases in the direction of the arrow 60, which makes kääntölaakeriraot 48 so that the pivot pins July 26 105 128 fitting a transfer and b to the position between. When this operation is continued, the slots 48 will eventually move so far that the pivot pins 26 will move to the pivot point b. The main body 20 then moves down to its normal position by gravity and springs 40, as shown in Figure 3. If the upper support arm 18 moves further down 5, it will act on the flap 22 and press it downwards, as already shown in connection with Figure 4.

There are several other preferred embodiments of the invention. Thus, the rear portion of the main body 20 preferably has a protective portion 62 which covers all openings in the rear surface of the protective cover 10. The shield portion 62 is suitably bent slightly upward to facilitate folding of the shroud 10 into the upper position (see Fig. 5). 1 and 2, reinforcing ribs 64 are also used at corners of the main body 20, which serve to prevent entanglement. although guards for taper shafts should not be used as step-15 boards and it is not advisable to use them as such, they are occasionally used by step-users as step boards. As a result, it is advisable to perforate the central flap 22 or otherwise make it easily identifiable and to affix warning labels to prevent stepping on the flap 22.

20

Claims (10)

A protective cover for a drive shaft (14) having a substantially U-shaped head portion (20) for covering the end of the drive shaft with a central portion formed from the top to the base branch and two laterally extending downward branches from the base branch (14). ) with a central notch (24) which can be closed by means of a pivotable flap (22) forming part of the protective cover, and that between the main part (20) and the flap (22) there are biasing devices which prestress the flap (22) upwards 10 to bring the flap (22) to the first position where it closes the notch (24). Cover according to claim 1, characterized in that the flap (22) is pivotally mounted on at least one pivot pin (26) and that the same pivot pin (26) acts as a pivot axis of the main part (20). 15 Cover according to Claim 2, characterized in that slots (48) are formed in each side portion of the main part (20) and that at least one pivot pin (26) extends at least up to the slots (48) and forms a pivoting bearing for the main part (20). 20 Cover according to one of Claims 1 to 3, characterized in that: • the biasing device comprises at least one spring pendulum (38) formed on the flap (22) extending with respect to the pivot point away from the closing portion of the flap; 46) and at least 25 one tension spring (40) connecting the two spring pendants (38, 46) to each other. • · * · Cover according to claim 3 or 4, characterized in that the end points of the slots (48) facing each other are located on either side of the line passing between the anchor point between the tension spring (40) and the flap (38) and the tension spring (40). through the anchorage point. »105128 Cover according to one of Claims 3 to 5, characterized in that the main part (20) can be pivoted in a normal operating position in which at least one pivot pin (26) is in the first end position of the slot (48); and a raised position in which the pivot pin (26) is located in a second end position of the slot (48). 5 Cover according to one of Claims 1 to 6, characterized in that the main part (20) can be pivoted between the basic position and the raised position; wherein the upper outer surface of the main body (20) is provided with at least one lifting tab (56) and the flap (22) is provided with at least one protruding lifting tab (54) which can be engaged with the lifting slot (56) by pressing the lifting tab (54) ) against one side to move the main body (20) from its raised position to its home position. Cover according to Claim 7, characterized in that the lifting tab (54) and lifting slit (56) are arranged such that when the main part (20) is moved further upwards from its raised position by the lifting tab 15 (54) such that the pivot pin (26) ) slides from one end of the pivot bearing slot (48) to its opposite end and causes the main part (20) to return to its normal operating position. 8 105128 Cover according to one of Claims 4 to 8, characterized in that the at least one flap hanger (38), the at least one main body hanger (36) and the pivot bearing slots (48) are • arranged to form a dead center structure such that the springs (40) ) achieve their maximum elongation when the main body (20) is positioned between its normal working position and its raised position. 25 Protective cover according to one of Claims 1 to 9, characterized in that the protective cover (10) covers the transmission shaft (14) of the vehicle equipped with a three-point coupling device and that the notch (24) and the flap (22) are dimensioned and positioned the upper support arm (18) of the device may affect only the flap (22), but not the head 30 (20). «10 105l28